Stoker tuyere



F. B. HALL STOKER 'I'UYERES Sept. 21, 1948.

2 Sheets-Sheet 1 Filed Dec. 12, 1942 Fig.1

' FRED B. HALL a2,- amw f Sept. 21, 1948. F. B. HALL 2,449,602

smegma TuYEhEs Filed Dec. 12.. 1942 I 2 sheets-sh: 2

FRED B. HALL Patented Sept. 21, 1948 2,449,602 s'ronnn 'rUYEan Fred B. Hall, Worcester, Mass., assignor to Riley Stoker Corporation, Worcester, Mass, a oorporation of Massachusetts Application December 12, 1942, Serial No. 468,860

invention relates to stoker tuyres, and more particularly to a tuyre construction for use with multiple retort underfeed stokers of the 6 Claims. (Cl. 11044) well known Riley type having reciprocable retort side Walls.

' When certain fuels are burned on stokers of this type there is a tendency for the combustion to be considerably more active directly above the tuyre rows than above the retorts, whereas a more uniform distribution of combustion activity isdesirabie in the interests of maximum capacity and cfificiency. It has heretofore been proposed to remedy this difficulty by utilizing so-called f'plate type tuyere blocks, which comprises web portions provided with ribs on one or both sides to form tuyere. openings, therindividual blocks being mounted side by side in planes substantially perpendicular to the upper margins of the retort side walls and the arrangement being such that some ofthe jets of air are directed transversely of 1.

the retorts. As heretofore proposed such plate type tuyre constructions have failed to remain in proper position on the stoker, or have interfereu, with the relative reciprocating motion of adjacent retort side Walls. In some cases the prior arrangements have been too expensive for practical use, and in other cases they have been subject to rapid destruction by the heat of the fuelbed.

It is accordingly one object of the invention to provide an improved plate tuyre construction particularly adapted for use with multiple retort underfee'd stokers having recipro-cable retort side walls. It is a further object of the invention to provide a plate tuyre construction which can be held firmly in position on the retort side walls, and which will in no respect interfere with the reciprocation thereof.

It is a further object of the invention to provide a .plate tuyere construction which will be comparatively simple and inexpensive to manufacture, and capable of operating efficiently throughout a long life of usefulness.

With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.

Referring to the drawings illustrating one embodiment of the invention, and in which like reference numerals indicate like parts,

Fig. l is a longitudinal section through one retort of a. multiple retort underfeed stoker, taken on the line l -l of Fig. 2;

Fig. 2 is a section on the line of Fig. 1; F 3 is a section on the line 33 of Fig. 2;

Fig. 4 is a perspective view of one tuyre block; Fig. 5 is a fragmentary perspective view of a slightly modified tuyre block; and

Fig. 6 is a perspective view of a bar forming a part of'th-e tuyre construction.

In the drawings there is illustrated a multiple retort underfeed stoker of the well known Riley type comprising a series ofparallel retorts l0 extending rearwardly from the front well ill of a furnace. Each retort is provided with a stationary bottom plate i2 and two horizontally reciprocable upright hollow side Walls or side bars is which slope downwardly and rearwardly. The rear ends oitheflside bars are connected to shoes 25 which are slidably supported upon a stationary structure H5. The rear portions of the side bars carry overfeed grates It. Any suitable and well known means may be provided for reciprocating the side bars of each retort relative to the side bars of adjacent retorts and for supplying fuel to the front ends of the retorts. The usual siftings strips iii are attached to the sides of the retort bottoms [2 to engage the ITIOVii'lg side bars and prevent leakage of the fuel. Air for combustion will be supplied under pressure to the space beneath the retorts in known manner, this air flowing upwardly through the hollow side bars The present invention provides an improved tuyre structure which is mounted on the retort side bars M to support the fuel bed thereabove and to distribute the combustion air. This struc- 1 ture includes 'a series of tuyre'blocks 2! each comprising an upright Web or plate 22 '(Fig. 4) having spaced ribs 23 thereon extending generally horizontally to form channels for the discharge of air from the inner edge of the block into the retort. At the bottom of theinner edge of the block there is provided a downwardly projecting 111g 24 which overlaps the inner surface of an upwardly projecting rib 25 (Fig. 2) on the upper edge of the side bar Hi to form a shiplap joint. This rib 25 is spaced outwardly from the inner surface of theside bar. The Webilfi is provided adjacent its upper edge with spaced upright ribs 2! arranged to direct some of the air upwardly. Between the horizontal ribs 23 and the upright ribs 27, adjacent the nose or upper inner portion of the block, there is provided a triangular rib or bass ill-which preferably projects from the Web a less distance than the ribs 23 and 21. This constructions-ewes to discharge air not only at both sides of the boss 29 but also across the face parent from the above disclosure.

of this boss, thus efiectively cooling the nose portion of the block and enabling it to withstand the severe heat conditions to which it is subjected in service. In order that the block may remain in use even after the nose portion thereof has been burned away, an angularly positioned rib 3| is provided adjacent the corner of the boss 29 remote from the nose of the block. Preferably both sides of the web 22 are provided with the same arrangement of ribs 23, 21, 29, and 3|.

Means is provided to hold the tuyere blocks 2| in the proper assembled relationship. For this purpose there are provided bars 33 each having two ribs 35 extending along its upper and lower edges respectively, and a rib 36 extending along.

its inner face. Each tuyere block is provided at its outer edge with a pair of opposed hooks 37 one of which is located directly beneath the other. The upper hook is positioned adjacent the top of the block and projects downwardly, whereas the lowerhook projects upwardly. At assembly these hooks embracingly engage the ribs 3%, the rear edge of the web 22 engaging the rib 35. Each of the bars 33 is long enough to connect with several of the tuyre blocks. The outer faces of the bars in adjacentrows are in rubbing contact, as indicated in Fig. 2, thus preventing any co-ntactor interference between the tuyere blocks 2! in adjacent rows. In order to prevent any possibility of interference between the bars 33 in adjacent rows, the end portions of their outer surfaces are beveled as indicated at 39 in Fig. 6.

In order to hold the tuyere blocks in place on the side bars M, a downwardly extending tail dl may be provided On the Web 22 to project downwardly into the side bar. Each of these tails M has an opening 42 therethrough for the reception of a rod d3 which is connected by a hook bolt 45 to the bottom of the side bar. Each of the rods 43 may extend through several of the tails M, as shown in Fig. 3, but it is not necessary that all the tails be engaged by the rods, since the bars 33 serve as connecting devices for adjacent tuyere blocks. Furthermore, the tails may be omitted entirely from certain of the blocks in order toavoid interference with transverse strengthening ribs 48 in the side bars M.

In some cases it may be desirable to provide upward extensions 56 on the webs 22 of certain of the tuyere blocks, in order to obtain a more positive rearward feeding of the fuel. These extensions 50 form shoulders which will enable the moving rows of tuyere blocks to push the fuel more effectively during their rearward travel. Because of the rearward inclination of the side bars, there will be substantially no tendency to drag the fuel forwardly on the idle stroke.

'The operation of the invention will now be ap- Fuel is delivered into the front ends of the retorts It] by the usual feeding devices. The reciprocating movements of the retort sides and tuyre blocks carry the fuel. slowly to the rear, while air flows past the tuyeres to support the combustion. The rib-s 23 direct a considerable portion of the air late-rally into the retorts and thus tend to maintain a more uniform rate of combustion across the stoker. The shallow triangular ribs 29 allow air to flow past the nose portions of the blocks in substantial amounts to prolong the life of these relatively exposed corners, and if they should burn away after long service the ribs 3] will still remain to prevent excessive sifting of the fuel and to permit continued operation of the tuyre blocks. The bars 33 not only hold the tuyre blocks in 4 correctly assembled relationship but they also provide smooth surfaces of large area for rubbing contact with the laterally adjacent bars, thus forming an effective seal between the sides of adjacent retorts. The assembled tuyere blocks are firmly held against the side bars by means of the rods 43 and the hook bolts 45. The lugs 24 and. rib 25 provide a shiplap joint which forms an effective air seal to prevent combustion from taking place too low in the retort. The construction is comparatively simple and inexpensive to manufacture and install.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. A tuyere block for an underfeed stoker comprising an upright web, a series of spaced ribs on the web extendin generally horizontally to form channels for the discharge of air from the inner edge of the block, spaced upright ribs on the web adjacent its upper edge, a triangular boss on the web adjacent its upper inner portion or nose, and an angularly positioned rib on the web adjacent the corner of the boss remote from the nose.

2. A tuyre block for an underfeed stoker comprising an upright web, a series of spaced ribs on the web extending generally horizontally to form channels for the discharge of air from the. inner edge of the block, spaced upright ribs on the web adjacent its upper edge, a triangular boss on the web adjacent its upper inner portion or nose and projecting from the web a less distance than. the horizontal and upright ribs, and an angularly positioned rib on the web adjacent the. corner of the boss remote from the nose. 7

3. An underfeed stoker comprising a retort side wall having an upwardly projecting rib extending alon the upper edge thereof and spaced outwardly from the inner surface of the side wall, and a series of tuyere blocks mounted on the upper edge of the side wall, each block including an upright web, a series of spaced ribs on the web extending generally horizontally to form channelsfor thedischarge of air from the inner edge of the block, and a lug projecting downwardly from the inner edge of the block in overlapping relation with the inner surface of the rib on the retort side wall, the lug extending along the said rib throughout the entire width of the block. 7

l. An underfeed stoker comprising two adjacent retort side walls arranged for relative reciprocation, a row of tuyere blocks mounted on the upper edge of each side wall, each tuyre block having an upright web, spaced ribs on the web to form channels for the discharge of air from the inner edge of the block, a downwardly projectin hook at the outer edge ofthe web and adjacent the top of the block, and an upwardly projecting hook at the outer edge of the web and directly beneath the first mentioned hook, and a bar extending past the outer edges, of the blocks in each row and embracingly engaged by the hooks to hold the blocks in as sembled relation, the bars for adjacent rows being in rubbing contact with each other.

5. A tuyre structure for an underfeed stoker comprising a series of juxtaposed tuyre blocks each including an upright Web having spaced airdistributing ribs adjacent its inner edge, a downwardly projecting hook at the outer edge of the web and adjacent the top of the block, and an upwardly projecting hook atvthe outer edge of the Web and directl beneath the first-mentioned hook, and a barextending past the outer edges of the webs and embracingly engaged by the hooks to hold the blocks in assembled relation.

6. A tuyere structure for an underfeed stoker comprising a series of juxtaposed tuyre blocks each including an upright web havin spaced airdistributing ribs adjacent its inner edge, a downwardly projectin hook at the outer edge of the web and adjacent the top of the block, and an upwardly projecting hook at the outer edge of the Web and directly beneath the first-mentioned hook, and a bar extending past the hooks, the bar having a rib on its inner surface for engagement with the outer edges of the webs and ribs on its top and bottom surfaces which are embracingly engaged by the upper and lower hooks respectively to hold the blocks in assembled relation.

FRED B. HALL.

REFERENCES CITED The following references are of record in the file of this patent:

Preston Oct. 11, 1938 

